Pakistani army and police investigators have began interrogating a serial killer who has confessed to murdering 100 children.

Javed Iqbal, 38, was brought before an anti-terrorist court in Lahore and remanded into police custody for two weeks.

He is now being questioned in the headquarters of the Crime Investigating Agency (CIA) amid tight security by police and army personnel.

Police are trying to discover more about Iqbal's motives and whether there might also be a possible commercial aspect to the abduction and abuse of the children, all boys between the ages of six and 16.

Mr Iqbal was arrested on Thursday, after walking into the Lahore offices of Pakistan's largest Urdu language newspaper, the Jang, offering to turn himself in.

Jang editor Shaheen Quereshi said Mr Iqbal wanted to write a confession, but was afraid police would try to kill him.

As he began writing, employees alerted Pakistan's military authorities, who sent more than 100 soldiers to surround the building.

His arrest came only hours after the capture, in the Punjab town of Sohawa, of two alleged accomplices who were trying to cash travellers' cheques belonging to Mr Iqbal.

It would appear that their arrest prompted Mr Iqbal to surrender.

After Mr Iqbal penned an initial letter of confession a month ago, police spent several days interviewing the families of missing children.

More than 80 were identified by relatives who either found their child's picture or recognised clothing from among the piles found in Mr Iqbal's house.

Police also found two barrels of acid - allegedly used to dispose of the remains of the victims.

"No regrets"

"I have no regrets. I killed 100 children. I was denied justice," Javed Iqbal told The News newspaper in Lahore shortly before he was arrested.

"I could have killed 500; this was not a problem. Money was not a problem. But the pledge I had taken was of 100 children, and I never wanted to violate this," he said.

Mr Iqbal told the newspaper that he was motivated by a desire for revenge against police, who he said beat him when they detained him for questioning into allegations of sodomising children in the 1990s. He was never charged.

"I was so badly beaten that my head was crushed, my backbone broken and I was left crippled," he said. "I hate this world.

"My mother cried for me. I wanted 100 mothers to cry for their children," the newspaper quoted him as saying.